Known in the art are DRM having translationally rotatable working members, wherein working chambers communicate with the discharge area after precompression occurs, e.g., compressors comprising a casing accommodating spur-gear rotors at least one of which has its teeth provided with grooves, while the teeth of the other rotor have projections mating said grooves (cf., e.g., U.S. Pat. No. 3,535,060, U.S. Pat. No. 4,457,680, U.S. Pat. No. 4,224,016).
Known in the art are also spur rotary compressors available from Ingersoll-Rand Company and having the following construction arrangement: drive is obtained from a master gear to the gears of the two-stage shafts arranged in a V-shaped manner; two compressor rotor spur-gear stages; an intake port disposed in the end covers and partly on a cylindrical boring of the casing; discharge ports are provided in the end covers; the discharge port is closed by the end face of a specially shaped rotor in the course of a compression stroke; the end of an internal (built-in) compression is fixed by opening the discharge port by the end face of one of the rotors (cf., e.g., “Resume of science and technology”, series “Pump and Compressor Building. Refrigerating Machinery Building” by P. I. Plastinin and T. M. Kalnin vol. 3, Moscow, VINITI 1986, pp. 83–85).
The above technical solutions suffer from the following disadvantages:                the DRM under consideration is not a versatile one due to its not being efficient as a compressor because communication between the shut-off space and the discharge area is established without precompression between the rotors. It is not also applicable as an ICE;        the DRM is not a compact one, since only a part of the sealing disk (i.e., a single tooth) is in action at every instant of time whereas the remainder part of the machine adds to the overall dimensions thereof;        the peripheral portion of the sealing disk contacts the central screw portion, and vice versa, which deteriorates the contact conditions and adds to friction effective therebetween, thereby affecting the efficiency and service life of the machine.        
The most pertinent to the present invention prior art is a DRM comprising a stator having a concentric effective area, and a main (driving) rotor. Said stator and said main rotor define at least one chamber-defining space there between. The DRM further comprises at least one driven rotor rotatable about its own axis which overlaps with the drive rotor axis, said driven rotor being partially deepened in a groove passing through the stator effective area and having at least one recess made across the perimeter thereof, said driven rotor dividing said at least one chamber-defining space into working chambers; inlet and outlet ports for the working fluid to pass, said ports being disposed in fluid communication with the working chambers. The DRM is made as a screw pump comprising a housing, a drive screw, and a toothed rotary sealing disk engaging with the screw. The disk teeth are engaged with the recesses defined between the screw ridges so as to provide a sealed contact therebetween. The teeth of the sealing disk have parallel side surfaces, triangular-shaped clearances being provided between said teeth.
The threaded screw portion is in its part formed as a shoulder or ridge which has a dimension in the direction of the screw rotation such that it corresponds to the screw displacement while moving the sealing disk from a position at which sealing is provided by one of the disk teeth, to a position at which sealing is provided by the next disk tooth (cf. USSR Inventor's Certificate No. 757,770).